One of the major trends in current research is the assessment and seismic retrofitting of existing RC buildings and civil engineering works. This requires better investigation and verification procedures. However, non-destructive testing (NDT) methods cannot be fully substituted for destructive test methods.
This database has been collected over many years of experimental programs and seismic vulnerability assessments of public and private RC constructions. It includes structures from seven regions of Italy.
Cost
Concrete is one of the most widely used modern building materials. It is a composite material that combines cement, sand and aggregates with water to create an artificial stone with a high level of strength. The material’s limited tension resistance, however, limited its use until steel reinforcement was introduced to the mix. The result is an effective structural system that resists bending moments by transferring the stresses to the surrounding concrete and limiting the stress concentration.
The cost of RC construction is influenced by the material and labor costs, as well as the design and construction methods. The cost of repairs associated with strengthening interventions should also be considered. Lastly, safety measures and professional fees should be included in the cost of the work.
Strength
Reinforced concrete (RC) is used to construct a wide range of structures. It is poured, sprayed, pumped, and grouted to form the building structure. It can also be cast in-situ. It is more durable than steel and can withstand a variety of stresses. It is also a good material for seismically vulnerable buildings.
In the field of investigation procedures for RC constructions, non-destructive tests are frequently used in combination with destructive test methods. However, the results of these tests are often unsatisfactory for existing RC constructions, and their reliability is questionable. This study considers a large database of samples from buildings and civil engineering works for which core drilling was performed. This database includes data from laboratory investigations and professional practice activities. The results of the analysis show that many current DT-NDT relationships for in situ concrete are not reliable.
Durability
A key factor that determines the durability of concrete structures is its exposure to harsh environmental conditions. Chloride attack is one of the most common causes of deterioration in RC structures, especially in marine and highway bridges. This damage accelerates the corrosion of steel reinforcing bars and can lead to spalling and cracking.
Multistory reinforced concrete buildings are used in many applications, from office complexes to heavy duty floors in factories. They are also used for marine and port structures, quay walls, piers and watchtowers. They are also used as foundations for commercial buildings and airport runways.
In recent years, there have been increasing demands for the assessment of existing RC buildings and civil engineering works. These structures were built before seismic guidelines were implemented and require a thorough evaluation. However, a number of existing investigation procedures are not suitable for the evaluation of RC constructions.
Flexibility
One of the major focuses of current research trends is the recovery and reuse of existing RC buildings and civil engineering works. These structures have in most cases been designed without seismic and modern standards and need assessment and retrofitting actions. The structural properties of concrete, particularly the strength and mechanical characteristics, play an important role in this process.
This study investigates the critical issues that occur in the investigation of existing RC constructions using non-destructive testing (NDT) and destructive test methods. It also evaluates the relationship between these methods and the in situ concrete characteristics.
The investigated data are based on a large database collected during several experimental programs and professional practice activities. It covers a wide range of RC structures including multistorey buildings, airport hangars and industrial structures.
Design
RC constructions can be designed to serve a wide range of applications. For example, reinforced concrete grid floors are widely adopted for office buildings and aircraft hangers. They are also suitable for marine structures such as wharfs, quay walls and watchtowers. RCC trusses and shells are preferred over steel trusses for power transmission lines. Similarly, RC poles are more commonly used than steel ones for TV transmission towers.
Investigation methods based on non-destructive tests (NDTs) are often adapted to RC constructions, but their reliability for existing structures has not been confirmed. This study focuses on the evaluation of these methods by considering a significant database that is gathered from experimental and professional activities. This database considers cylindrical samples extracted from existing RC structures by core drilling.
